The present invention relates to slag cement, and more particularly to drilling and cementing boreholes.
Grouting with fine ground slag cement is known. Such grouting is disclosed in Clarke, U.S. Pat. No. 4,761,183 (Aug. 2, 1988) and Clarke, U.S. Pat. No. 5,106,423 (Apr. 21, 1992). The '423 patent also discloses petroleum as an area of utility for the cementitious slurries described in the invention.
The teaching of Clarke follows conventional wisdom that the advantages flowing from the use finely ground hydraulic materials can justify the grinding expense. However, the difficulty of such grinding is quite great. The particle sizes of even normally ground hydraulic materials are generally in the micron range. Relative to slag broadly, Clarke '423 teaches that less than 3%, preferably less than 1.5%, and most preferably, no particles are larger than 7.8 microns in diameter should be present.